1. Field of the Invention
The present invention relates to a cooling structure, and is more particularly concerned with a device for cooling integrated modules and, in particular, for cooling a plurality of integrated modules combined to form logic cards.
2. Description of the Prior Art
Increasing miniaturization of integrated modules to form very large scale integrated (VLSI) modules and, in conjunction therewith, the high packing density result in a high heat emission of logic cards which are equipped with a plurality of such integrated modules, which can easily lead to a transgression of the temperatures which are permissible for the integrated modules. Such logic cards must therefore be provided with one or more cooling members for thermal protection.
It is known in the art to employ large-surface metal plates as cooling members for such logic cards, the metal plates emitting the waste heat of the integrated modules either to the air surrounding the modules or to hollow bodies traversed by liquid or gas. It is therefore known, for example, from U.S. Pat. No. 3,993,123 to provide a device having a plurality of heat-generating electrical modules which are mounted on a base. A heat dissipation housing seals and surrounds the heat-generating components. The wall of the housing lying opposite the base exhibits elongate, cylindrical openings in the direction toward the heat-generating components. A spring element, which is supported against the inner end of the opening, is located in each such opening of the housing. Further located in each opening is a heat-conductive element in the form of a piston which is dimensioned such that only a narrow gap remains between the outer walls of the openings and the piston. Each spring element presses the heat conduction element against one of the heat-generating components. A thermally conductive, inert fluid is located inside of the housing and fills all gaps and cavities thereof. The heat is dissipated from the housing by way of external dissipation structure. Every individual electronic module is individually cooled by such techniques or by techniques such as known from the European patent application No. 0001 153 as a further development of this general concept. What is disadvantageous, given this type of cooling structure, however, is that the heat from the chip of the integrated module flows only over punctiform contacts into the die and, from there, into the actual cooling member by way of a gas path. The punctiform contact between the integrated module and the metal die and the gas path between the metal die and the cooling member have a relatively high thermal resistance. This structure, moreover, requires a great expense.